Subjects were recruited from the ALIVE study, a longitudinal study of 2,000 IV drug users. The instant study is examining the natural history of HCV , and the effect of comorbid conditions (HIV, alcoholism, drug addiction, etc.) , upon the liver. Liver biopsies have been performed on 210 subjects from ALIVE who previously had been identified through ( and verified ) through anti-body testing. The subjects had also been followed for several years with liver functioning tests, and divided into three categories: chronically elevated ALT, intermittently elevated ALT and normal ALT. Biopsy slides have been reviewed by a pathologist , grading them to four categories using the Knodell model. The slides are currently being reviewed by a second pathologist using the same criteria. Final results are pending the second review. Preliminary planning includes conducting a second round of liver biopsies on the 210 subjects, beginning three years after the first, in the fall of 1999. Subjects will again be paid $50 for undergoing the procedure, as they were for the first.